Membrane lipoteichoic acids (LTA) are synthesized and excreted by a variety of oral bacteria. We shall study the structure, metabolism, excretion, function and control of the metabolism of LTA in these organisms. The LTA's which have been strongly implicated in a number of oral diseases are synthesized by enzymatic reactions that do not occur in animal tissues. This metabolic difference offers the possibility of a new chemotherapeutic approach to oral disease.